The Long (Over)Haul
Part VI: Putting fire in the hole and fury on the dyno
Dave Verna - August 22, 2013 10:00 AM
(Left to right): Edelbrock Super Victor, Victor 340, and RPM Air Gap. The first two are single plane intakes and will go on the ported heads, while the dual plane air gap is going on the stock set of heads.
Our first setup, the mildest one, is the stock heads, and air gap dual plane intake.
We topped off the fuel cell with 93 octane and bolted up the 15/8-inch long tube headers. These would be a typical header for a mild to moderate set-up in a street/strip car.
With the Holley 750 Ultra HP bolted up and a few cranks, we hit the ignition switch! The 430 came alive with a few blips of the throttle. With no signs of leaks and no other issues, we were set.
With the break-in proceeding, all eyes are on all the gauges. Every engine builder has their own method of break-in. The plateau hone helps speed up the process of seating the rings against the cylinder walls.
We made the pulls on this set-up from 3,000 to 5,600 rpm. How’s 511 horsepower at 5,400 rpm and 566 lbs-ft at 4,200 rpm sound? The torque average was 515 lbs-ft, carrying over 500 for most of the pull.
We tried a few other Holley carbs, such as the 830 HP and the 950 HP; we were within one horsepower of each other after a few jet changes to get it dialed in.
A fresh coat of paint and the hand-ported heads, Victor 340 intake, 15/8-inch headers and the same COMP XR 280R. With 562 hp at 6,000 rpm and 557 lbs-ft of torque at 4,600 rpm, the power band moved up with a single plane and a better breathing head; we pulled the engine from 3,200 to 6,200 rpm.
This is our wild set-up. The cam is bigger, the heads flow more, bigger intake, the headers are a 1¾ x 17/8-inch-inch step and the Moroso vacuum pump was bolted on. This one is running a Holley 1000 HP carb.
Switching to Royal Purple full synthetic oil and the vacuum pump will make more power, but only if there are no leaks.
We spun the last set-up to 7,000 rpm. With 627 hp at 6,500 rpm and 560 lbs-ft at 5,000 rpm, the torque stayed about the same but moved up in rpm with the larger intakes. Power came on at 34 degrees timing and jetting the big Holley with 88s in front and 90s in the rear.
Thanks to Neal, Al Sr., and Al Jr. of Fonse Performance for all their hard work. We appreciate their sticking with us over the long haul!
Torque curves are similar but move up and down the rpm range. Horsepower-wise, the combination of the cams, intakes, and heads will adjust the power levels, depending on how much air you can get into the engine.
After the initial break-in period, a filter cutter is your new best friend. You’re looking for assembly lube, and also metal particles, shavings and any other junk. You will find anything you missed in the cleaning process.
The remaining oil in the bottom of the filter will show you the condition of the engine. The oil is clean with a few small specks; you will never have perfectly clean oil.
We used a telescopic magnet to get into the folds of the filter. After this, we cut it and pressed it in a vise opening the folds to inspect every pleat.
Hopefully, you have been reading and learning through every step of our long journey.
From the beginning, we have preached over and over about planning your work and working your plan. This rings true more than ever when you fire up your new engine for the first time. Nothing short of perfection needs to be attained when you are ready for the initial firing. One mistake can cost you the engine, so this is no light matter.
In the car, on the dyno, or on a run stand, you need the initial fire up to be as immediate as possible.
Our goal was to have a relatively boring morning while we did our initial fire up and break in. You need to keep in mind that all bases need to be covered beforehand so nothing pops up while you are trying to fire the new baby up for the first time.
Make sure everything, even a brand new carb, is checked for leaks before you try to fire the engine, make sure there are no bolts loose and a few rounds of fluid checks never hurt. The potential for you to miss something now is high, as most are excited to fire the engine. Patience needs to prevail in order to make sure you have a happy, healthy engine!
A checklist is a great place to start, as more often than not we hear of how things start to go haywire and proceed to go downhill from there. Young or inexperienced enthusiasts will try to get a new engine to fire, filling cylinders with gas, dealing with overheating, major leaks, and improper tuning, all of which can wreak havoc on a new engine as well as the enthusiast and dyno owner.
A good rule of thumb is when things start to go bad, just shut it down! It never hurts anyone to check over and over before your initial fire up.